[CQ-Contest] re:Clicks-REAL numbers.

[Pete Smith]

At 11:00 AM 3/9/01 -0800, George Cutsogeorge wrote:
 >
 >Here are some keying test results done with real radios and an HP spectrum
 >analyzer.  The radios were set up at full output power and were keyed at 40
 >WPM.  The spectrum analyzer was setup with a narrow bandwidth and very slow
 >sweep time.  The dB levels given were measured at an offset of 1 kHz on each
 >side of the carrier.  (Total bandwidth = 2 kHz.)
 >
 >Radio        dB down at +/- 1kHz
 >
 >Omni VI+           -50
 >1000MP            -46
 >IC765                -44
 >Test                   -51
 >
 >The Test was done with an HP8640B signal generator keyed on and off at 40
 >WPM with a rise and fall time of 5 mS.
 >
 >This data shows that there really are sidebands out there which will be
 >heard by adjacent channel receivers.  This is a fact of life.  For example:
 >An Omni VI+ is sending 40 WPM and is S9 +30 dB on tune.  One kHz away his
 >sidebands (clicks) will be down 50 dB, or about S6 to S7 on a calibrated
 >meter (not a typical S meter).  Since the receiver filter also has a finite
 >bandwidth even with the best filters, the transmitted signal will appear to
 >be even wider.  This assumes there is no blocking or IMD taking place in the
 >rx or excessive phase noise in either tx or rx.  If there is, he will appear
 >wider yet.
 >
 >It's interesting to me to see how little difference there is between these
 >radios.  Thanks for the suggestion N0AX.

It'd be interesting to know how W8JI's modified FT-1000D would fare in the
same test.

73, Pete N4ZR
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